Production of preliminarily shaped annular blanks



Oct. 20, 1936. H. EDELMEIER PRODUCTION OF PRELIMINARILY SHAPED ANNUBARBLANKS- Filed Sept. 21, 1934 a wv a rm .mh v: ..n w. T uh A E L .mu

v mm

I 10 usually produced press having a plurality of '30 product isfrequently faulty.

' Patented Oct. 20, 1936 UNITED STATES PRODUCT N OF PEELIMINARILY ANNULl SHAPED AR BLANKS Edelmeier, Uerdingen-on-the-Rhine, Germany, assignmtothe firm ltingfeder Gesellscliaft mit beschrinkterHaftung,'Uerdingenon-the-Rhine, Germany 7 Application September 21,1924, Serial No. 744,907

InG

ermany December 9, 1932 4 Claims. (Cl. cal- 156) My invention relates tothe production of preshaped annular blanks-adapted to be rolled out forthe manufacture of spring rings for the socalled ring springs described,for instance, in the 5 United States Patents Nos. 1,501,220 and1,515,346, or of rings having similar predetermined surfaces orcross-sections of a relatively great axial height and a relatively smallradial thickness. Such preliminary annular blanks are from initial blanksections which are, for example, cut from bars or rolled billets bydeforming or stamping and preliminary and final punching of blanksections in a v punches and dies.

The rolling out of these preliminarily shaped annular blanks thenusually takes place on a suitable ring rolling mill of well-knownconstruction. Heretofore, the pressing of the said preliminary annularblanks has been performed so as to obtain preliminary blanks whosecross-sectional shape corresponds as much as possible to the desiredcross-section of the finished spring rings or the like, i. e. havingplane and cylindrical circumferential surfaces which are as flat aspossible. The subsequent rolling out of such blanks necessitates aconsiderable amount of work during the rolling, and the rolls aresubjected to very great strain, causing rapid wear of these expensivetools. In spite of this the A chief object of my invention is so topreshape the annular blank that the work required during rolling isreduced to a minimum, and only light rolling pressure is required,whereby the strain and, consequently, the wear on the rolls isconsiderably reduced.

According to my invention the deforming or stamping and the preliminaryandflnal punching of the initial blank section is so performed as toproduce a preliminary annular blank having a cross-sectional shape whichis overall or on all sides arched or polygonal or arched and polygonal.For instance, the outer and inner surfaces as well as the two endsurfaces of the blank may be curved convexly and merge into one anotherby rounded portions. Such a preliminary annular form seems to becontrary to the requirements for the rolling out of the final cross-sec5o tional" shape of the rings, for example of rings for ring springs,because the corners or edges of the latter are sharp and its inner orouter circumferential surfaces, respectivel are planeor evendifferently, i. e., concavely curved. How- 55 ever, experience hasproven that the above-mentioned advantages are in fact completelyachieved during the rolling.

- In performing my manufacturing process, I subject the initial blanksection successively to a stamping or deforming operation and prelimi- 5nary and final punching operation in a plurality of dies arranged in'one or more suitable presses.

- In order to bring the punches into contact with the heated blank onlyfor a short time, all punches dies, whereby the placing of the annularblank in the lower dies of the press or, should there be no specialdies, its centering on the lower plate of the pressing device with theaid of a stop, is materially facilitated. Owing to the arrangel5 ment ofthe punches in the upper dies, it is necessary that the blank should beturned through 180 degrees between each pressing operation.

.The annular form of the blanks according to my invention offers theadvantage that the de- 20 sired shape of the blanks can be obtainedduring pressing without great pressure, because it is no longernecessary to press the material into sharp corners of the dies.Moreover, the formation of burrs is avoided if the hollow space of thedies be 5 somewhat greater than the volume of the material to bedeformed. The diameter of the punches is made as small as possible inorder to make possible a high ratio of deformation in the rolling mill,whereby ring is given a tangential disposition which increases thedurability of the material in spring rings. Owing to the short timerequired during which no appreciable consumption of heat occurs, toproceed directly with the rolling process, 35 without any intermediateheating, or a heating furnace may be arranged between the press and therolling mill if it is desired to complete the heating of the blanksbefore the rolling process.

The production of the preliminarily shaped annular blanks by the processaccording to the invention will hereinafter be more particularly.described with reference to the accompanying drawing, which illustratesa constructional example of the pressing tools, and wherein Fig. 1 showsin vertical longitudinal section a press for performing three workingstages on the blank, prior to the performance of the pressing stroke,

Fig. 2 is a similar section showing the dies and blanks aftertermination of the pressing stroke,

Figs. 3 and 4 show, by way of example, two preliminarily shaped annularblanks in crosssection and on a larger scale, and

Fig. 5 shows, by way of example and in crossarevpreferably arranged inthe upper 0 the grain in the rolled section, the ed ring of a ringspring produced from the preliminarily shaped blank.

In the lower or base part i of the press are arranged the pressure plate2, the centering punch 3 and the lower die t, for the three stages, withwhich are associated the upper pressure plate it with the punches i andit, and the upper die it with the punch it, all or which are secured inthe upper or head part 5 of'the press. as is well known in presses ofthis type, the base part i is stationary and the head part b isvertically guided and moved up and down with respect to the saidstationary base part, by means of a suitable driving mechanism which isalso well known and needs, therefore, no particular description or 11-lustration for one skilled in this art.

The initial blank section iiwhich has been severed in any well knownmanner from 2, rolled billet or a bar, for instance by a suitable saw orhot shears, and has then been duly heated in any suitable and well knownfurnace, is placed on the pressure plate 2. In the pressing operation,the punch l is impressed into the .initial blank section ii and forcesit apart, and the section is at the same time upset or stamped by thecooperation of the lower plate 2' and the pressure plate 6 and therebyformed into the intermediate shape it.

The blank 12 produced in this first working stage is, after being turnedthrough 180 degrees, placed in the second working position upon thecentering punch 3 so that the second working stage may becarried out.During the second pressing stroke, the bottom i3 is stamped out of theintermediate blank I! by the punch 8 secured in the head 5. In order tofacilitate this operation, the punch 8 is made cylindrical at thebottom, while; in all other respects, its form is epnical, so thatthe-hole in the blank I4 is widcried in the known manner. In this secondworking stage, the' blank is somewhat increased in its external diameterand further reduced in height until it assumes the form M.

The blank is again turned through 180 between the second and thirdworking stages. In this latter pressing operation, substantially onlythe circumferential surfaces of the blank are pressed, so that anannular blank i5 is produced, the outer and" inner circumferentialsurfaces it of which are convexly curved, as shown in Figure 3. The endsurfaces I! of the blank l5 are also con-= vexly curved by suitableformation of the bases ii of the dies 4 and 9. Since the curvedtransitional portions I! of the bases ll of the dies 4 and 9 merge intothe contour of the punch it, the circumferential and end surfaces It andM, respectively, of the annular blank it also graduan angle to aosaoorally merge into one another by curved surfaces it, as shown in Fig. 3.Instead of this shape oi. the blank it comprising curves, it may bepolygonal as shown at iii in Figure l. The cross-sectional surface islimited by curved and broken lines. The preliminarily shaped annularblank it produced on the press is immediately rolled outin a suitablering rolling mill, for example to form the inner ring 22 of a ringspring (see Fig. 5). Such ring rolling mills are well known in this artand no particular description and illustration It is obvious thatvarious changes may be made in the shape of the preliminary annularblank shown and described, as well as in the process and device forproducing the same, without departing from the spirit of my inventionand the scope of the claims.

What I claim, is:-

1. The process of producing metallic rings of relatively large axialwidth and relatively small radial thickness, which consists in swagingand punching a solid metal. blank into an annulus of a substantially.square cross-section with all four faces bulgedoutwardly and with itsinside and outside-faces substantially parallel to the axis of theannulus, and then: subjecting the annulus to the action of opposedrollers working upon the inside and outslde'faces of the annulus.

2. The process claimed in claim 1, in which the said swaging andpunching operation includes the step of removing from the annulus theedges between adjacent bulging surfaces of said annulus, wherebytheindividual bulging surface of the annulus smoothly merges in theabutting bulging surfaces of the same.

3. The process claimed in claim 1, in which the said swaging andpunching operation includes the step of subdividing and transformingeach of said four bulging surfaces of the annulus into a plurality ofplane peripheral surfaces disposed at one another, an edge being thusproduced at the line of juncture of each pair of said plane surfaces,whereby each of said bulging surfaces of the annulus is given an angularoutline. i

i. The process claimed in claim 1, in which the said swaging andpunching operation includes the step of subdividing and transformingeach of said four bulging surfaces of the annulus into a plurality ofcurved peripheral surfaces disposed at an angle to one another, an edgebeing thus produced at the line of juncture of each pair of said curvedsurfaces, whereby each of said bulging surfaces of the annulus is givena curved and angular outline.

' HANS EDELMEIER.

